Apparatus for improving the quality of the independent line of sight when sighting with direct-sighted weapons

ABSTRACT

Apparatus for the control of the sight on a direct-sighted weapon which in respect of at least one axis of rotation of the sight electromechanically coupled to the weapon, whereby the weapon operator manually acts upon the orientation of the optical line of sight by integration of the control speeds, and where difference angles corresponding to the fire-control values calculated by the computer of the weapon can be introduced between the sight line and the axis of the weapon, and signals from reference elements on the weapon are made use of for the determination of difference angles between the actual position and the desired position.

States Patent [1 1 Teiling [451 Oct. 23, 1973 {75] Inventor: Carl Torbern Teiling, Lidingo,

Sweden [73] Assignee: AGA Aktiebolag, Lidingo, Sweden [22] Filed: Apr. 7, 1972 [21] Appl. No.: 241,995

[30] Foreign Application Priority Data Apr. 8, 1971 Sweden. ..'....Il.l42/7T [56] References Cited UNITED STATES PATENTS 3,019,711 2/1962 Bailey et al. 89/41 M COMPUTER 3INTEGRAT0R Primary Examiner-Stephen C. Bentley Attorney-Lawrence l. Lerner et al.

[57] ABSTRACT Apparatus for the control of the sight on a directsighted weapon which in respect of at least one axis of rotation of the sight electromechanically coupled to the weapon, whereby the weapon operator manually acts upon the orientation of the optical line of sight by integration of the control speeds, and where difference angles corresponding to the fire-control values calculated by the computer of the weapon can be introduced between the sight line and the axis of the weapon, and signals from reference elements on the weapon are made use of for the determination of difference angles between the actual position and the desired position.

I l I l COMPUTER GYRO 6 u PAIENIEBnm 2 3 I975 SHEET 10F 2 EEESER Pom mmSmEou PATENIEUum 23 1915 SHEET 3 BF 2 l m 8 2:6 -1 -liowomsm 8 N w 22 Q #2 9 9 mm F 8 m 9 Q/QU @5228 9 M. m hw 6m g m E 23 APPARATUS FOR IMPROVING THE QUALITY OF THE INDEPENDENT LINE OF SIGHT WHEN SIGHTING WITH DIRECT-SIGI-ITED WEAPONS CONVENTION PRIORITY This is a convention application based upon Swedish Patent Application No. 4652/71, filed Apr. 8, 1971 by AGA Aktiebolag.

FIELD OF THE INVENTION The present invention relates to an improvement in apparatus which is required or used so as to make it possible for certain direct-aimed weapons to have a socalled independent line of sight. A description of the problem and a solution thereof are reported in the Belgian Patent 758,195.

The basic concept of this invention utilizes the firecontrol values (determined in a non-rotating system of coordinates) to constitute the vectorial difference between the (a) sighting of the weapon and (b) the movable sight in relation to the weapon. These fire-control values are transformed in their coordinates to, and are put into effect by, the system of coordinates which is defined by the axes of rotation of the weapon and of the optical device respectively. These are as a rule rotated in relation to the earth-bound system. Furthermore derivatives are formed of these fire-control values in the non-rotating system which are likewise transformed to the said weapon-bound system, or equivalent data is formed in a different manner. These constitute the control speeds of the servo equipment of the weapon and should be integrated with space-bound reference, e.g. by means of speed-monitoring gyroscopes.

Provided this integration statically and dynamically is fully currect, and takes into account the principle that the deflection of the optical line of sight takes place quickly, the desired result is obtained, namely that the line of sight remains steady, in space, independently of variations in the fire-control values.

In many cases, almost as a rule, the servo equipment which should accomplish the integration of the speed control on the weapon, is relatively slow due to the fact that the load consists not only of the weapon but, e.g. in the case of tanks, also of the whole turret. The load varies moreover with friction, slope of the ground etc. It is difficult therefore, often almost impossible, dynamically to synchronize the servo mechanisms of the weapon and of the optical device with respect to each other so that their movements become identical and aligned.

It is known that when weapons are controlled by such a servomechanism system, the difference between desired and actual speed, for example, can be integrated by means of a special electronic integrator, the output signal of which thus signifies the angular difference between desired and actual values, that is to say the instantaneous angular difference. The desired value is identified in the present case as the sum of the desired position of the line of sight, supplied by integration of the speed or speeds of control from the handwheel or handwheels of the weapon operator, and the desired speed on the fire-control data determined according to the above. The actual value is the integrated output speed, in this case measured by the speed-monitoring gyroscope, the so-called rate-gyro.

SUMMARY OF THE INVENTION The present invention is characterized in that the output value of the integrator is interpreted as the fault position of the weapon, which by virtue of the mechanical coupling between weapon, and gun-sight also acts upon the optical line of sight, which therefore isfaultily directed by the corresponding angle, and in that this fault position is added to the fire-control angle, transformed in its coordinates. In the coordinate in question, the servomechanism which controls the optical line of sight in relation to the weapon is so synchronized that it responds to the desired angle signal so produced at a speed which is high in relation to the speed of the servomechanism of the weapon. The following effect, which in principle is quite independent of the servomechanism problem, is observed as an additional use to be made of the positional fault of the integrator, as defined above. During the transport of the vehicle over uneven ground the weapon seeks to maintain a position in space which is determined by the function of the integrator defined above. The aforementioned deficiencies cause deviations to occur irrespectively of whether variations in the fire-control data exist or not. In each case it is noted that when the output value of the integrator is zero the servomechanism fault is also zero and, in the present case, the weapon is ideally sighted in relation to the target is controlled by the pointer.

When firing during movement is to be carried out, the exact firing must take place when the output value of the integrator is zero.

It is obvious to those versed in the art how the adoption of this additional condition should be accomplished in the electrical mechanism for the firing, initiated by the pointer.

The invention will be illustrated by the enclosed figures which show two embodiments of the invention. For the sake of simplicity only one control coordinate has been drawn out.

DETAILED DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic showing of one embodiment of the present invention; and

FIG. 2 is a schematic showing of a second embodiment of the present invention.

The handwheel 15 in FIG. 1 is turned by the operator. Utilizing a potentiometer l, a voltage 2 is obtained which is proportional to the rotation of the handwheel and in the system represents the desired speed of the line of sight. This is fed first to an integrator 3 and secondly to a summator 4. The latter acts upon the servomechanism of the weapon which comprises a motor 16 and a gyro 6. Signals proportional to the control speed 5 of the angle of delivery obtaines from a computer and the voltage 7 obtained from the gyro 6 representing the instantaneous angular speed of the weapon are supplied to the integrator 3. The output value 8 of the integrator represents the integral of the sum of the two control speeds supplied less the instantaneous speed of the weapon (the actual speed), that is to say the fault angle. By means of this coupling, the speed of the weapon is controlled in a well-known manner by the sum of the control speed put into effect by the operator and the speed of the angle of delivery.

The optical servomechanism, consisting of the motor 12, the angle monitoring element (the potentiometer l3) and the load 14 is controlled by the signal proportional to the angle of delivery from the computer R7 to which is added the fault angle signal 8. The summation is done in a summator 9 which acts upon the motor 12. A signal 11 from the potentiometer 13 is also supplied to the summator 9.

It will be understood from what has been said above that this sum represents the desired position of the line of sight in relation to the instantaneous angular position of the weapon. In relation to the target (terrain) the line of sight therefore simply depends on the desired position controlled by the pointer. This property fully defines the concept of the independent line of sight.

The angular fault signal 8 is also supplied to the device 18, if so desired. The latter forms in a manner known to those versed in the art, a logical output signal, indicating when the fault signal approaches zero and the value of the fault signal defines a suitable moment for firing.

In connection with FIG. 1 an embodiment has been described where a so-called rate-gyro was used. In FIG. 2 an embodiment is shown which makes use of other types of gyro and these are exemplified by a so-called speed-integrating gyro.

The functions in FIG. 2 which can also be found in FIG. 1 have the same designation in both figures.

The operator works the handwheel 15, whose rotation via the potentiometer l is turned into a voltage 2 representing the desired angular speed (desired-speed) of the line of sight in question. The computer 17, has an output signal 5 representing the desired speed which signal is added in the summator 19 to the voltage 2 which represents the desired angular speed. From the summator 19 a voltage representing the desired speed of the weapon is obtained. This voltage 25 is translated in a directional gyro 20 to a proportional torque which precedes the position of the gyro rotor on the side in a conventional manner. The cardan system of the gyro is appropriately so arranged that the directional axis is perpendicular to the axis of the firing barrel and the balance axis is parallel to the elevation axis of the weapon.

When the respective angle monitors of the gyro for the balance axis and the directional axis indicate zero the torque vector of the gyro rotor is therefore parallel to the axis of the fire barrel.

The directional gyro 20 consists of a directional motor 21 and an angular transmitter 22. The signal 26 from the directional gyro is supplied to the amplifier 23 on the servomechanism and from there to the servomotor 16. The signal 26 from the directional gyro represents the difference between the desired and the actual direction, where the desired direction is defined by the rotor and the actual direction by the fire barrel.

This signal 26 is supplied also to a summator 9, whose function has been described in connection with FIG. 1. This summator is furthermore coupled to the optical servo mechanism 12, 13, as has been described above. The sum signal from the summator 9 is translated in the above described manner by the optic servo device 12, 13 to an angle which deflects the line of sight for the load 14. The arrows 24 in FIG. 2 symbolize the action on the servomotor 16 by the directional gyro 20.

Although this invention has been described with respect to its preferred embodiments, it should be understood that many variations and modifications will not be obvious to those skilled in the art, and it is preferred, therefore, that the scope of the invention be limited, not by the specific disclosure herein, only by the appended claims.

What is claimed is:

l. Apparatus for a direct-sighted weapon operative to control the sight thereof relative to the position of the weapon which is electro-mechanically coupled thereto, in at least one axis of rotation, said apparatus comprismg:

a. a first motor driven load operative from a first reference signal and includes a first servo feedback loop;

b. a second motor driven load operative from said first reference signal and including a second servo feedback loop having a faster response time than said first servo feedback loop;

c. line of sight speed indicating means;

d. integrating means responsive to said line of sight speed indicating means and the feedback signal of said first servo feedback loop to produce said first reference signal.

2. The apparatus for a direct-sighted weapon of claim 1 wherein:

said first motor driven load is a weapon and said second motor driven load is a gun sight.

3. The apparatus for a direct sighted weapon of claim 2 including computer means for supplying a signal proportional to the angle of delivery to said second servo feedback loop and to said integrating means.

4. The apparatus of claim 1 wherein said first servo feedback loop includes directional gyro.

5. The apparatus of claim 1 wherein said line of sight speed indicating means includes a handwheel and potentiometer combination whose rotation is converted into a voltage representing the desired angular speed of the line of sight.

6. The apparatus of claim 3 including a firing means operative to be actuated when said first reference signal drops to zero. 

1. Apparatus for a direct-sighted weapon operative to control the sight thereof relative to the position of the weapon which is electro-mechanically coupled thereto, in at least one axis of rotation, said apparatus comprising: a. a first motor driven load operative from a first reference signal and includes a first servo feedback loop; b. a second motor driven load operative from said first reference signal and including a second servo feedback loop having a faster response time than said first servo feedback loop; c. line of sight speed indicating means; d. integrating means responsive to said line of sight speed indicating means and the feedback signal of said first servo feedback loop to produce said first reference signal.
 2. The apparatus for a direct-sightEd weapon of claim 1 wherein: said first motor driven load is a weapon and said second motor driven load is a gun sight.
 3. The apparatus for a direct sighted weapon of claim 2 including computer means for supplying a signal proportional to the angle of delivery to said second servo feedback loop and to said integrating means.
 4. The apparatus of claim 1 wherein said first servo feedback loop includes directional gyro.
 5. The apparatus of claim 1 wherein said line of sight speed indicating means includes a handwheel and potentiometer combination whose rotation is converted into a voltage representing the desired angular speed of the line of sight.
 6. The apparatus of claim 3 including firing means operative to be actuated when said first reference signal drops to zero. 